大约有 26,000 项符合查询结果（耗时：0.0500秒） [XML]
Is it a good idea to index datetime field in mysql?
I am working on designing a large database. In my application I will have many rows for example I currently have one table with 4 million records. Most of my queries use datetime clause to select data. Is it a good idea to index datetime fields in mysql database?
...
Is there any difference between the `:key => “value”` and `key: “value”` hash notations?
Is there any difference between :key => "value" (hashrocket) and key: "value" (Ruby 1.9) notations?
5 Answers
...
Multiple columns index when using the declarative ORM extension of sqlalchemy
According to the documentation and the comments in the sqlalchemy.Column class, we should use the class sqlalchemy.schema.Index to specify an index that contains multiple columns.
...
Hex representation of a color with alpha channel?
Is there a W3 or any other noteworthy standard on how to represent a color (including alpha channel) in hex format?
5 Answe...
How to download/checkout a project from Google Code in Windows?
How do I download a ZIP file of an entire project from Google Code when there are no prepared downloads available?
6 Answe...
How can I check if a key is pressed during the click event with jQuery?
I would like to catch a click event with jQuery and be able to tell if a key was pressed at the same time so I can fork within the callback function based on the keypress event.
...
Rails: Check output of path helper from console
Rails defines a bunch of magic with named routes that make helpers for your routes. Sometimes, especially with nested routes, it can get a little confusing to keep track of what URL you'll get for a given route helper method call. Is it possible to, using the Ruby console, see what link a given help...
How to output messages to the Eclipse console when developing for Android
How can I print messages (like a flag) to the Eclipse console (or log) when developing and debugging an Android app
5 Answe...
bash assign default value
I thought I could use this feature to write ${LONG_VARIABLE_NAME:=hello} instead of the longer LONG_VARIABLE_NAME=${LONG_VARIABLE_NAME:-hello} , but now bash also tries to execute 'hello' and that gives a command not found. Any way to avoid that? Or will I have to stick to the latter? Can someone...
How do I negate a test with regular expressions in a bash script?
...ke to negate a test with Regular Expressions. For example, I would like to conditionally add a path to the PATH variable, if the path is not already there, as in:
...